研究者詳細 - 木村　幸敬

論文 - 木村　幸敬

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Oxidation of linoleoyl residue of its trehalose ester in an aqueous solution 査読

Jie Chen, Yukitaka Kimura, Shuji Adachi

FOOD SCIENCE AND TECHNOLOGY RESEARCH 12 ( 3 ) 163 - 166 2006年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：KARGER

6-O-Monolinoleoyl trehalose synthesized by the immobilized-lipase-catalyzed condensation of linoleic acid and trehalose was dissolved in water at various concentrations, and its oxidation processes were then measured at 35 degrees C based on both the decrease in the linoleoyl residue and oxygen consumption. The stoichiometric coefficient of oxygen to the linoleoyl residue was in unity except during the late stage of the oxidation. The oxidation process could be expressed by the rate equation of the autocatalytic type. The rate constant was higher for the higher substrate concentration, but it was not in proportion to the concentration at substrate concentrations higher than its critical micelle concentration. These results suggested that the migration of oxygen into the hydrophobic core of the linoleoyl residues through the hydrophilic trehalose layer of the linoleoyl trehalose micelles affected the overall oxidation rate of the linoleoyl residue.

Thermal inactivation of immobilized lipase in 1-alcohols 査読

Yayoi Yoshida, Yukitaka Kimura, Shuji Adachi

Journal of Bioscience and Bioengineering 102 ( 1 ) 66 - 68 2006年7月

記述言語：英語掲載種別：研究論文（学術雑誌）

The thermal inactivation of immobilized lipase from Candida antarctica in 1-alcohols with four to eight carbons at various temperatures could be well expressed using a model in which heterogeneity in the susceptibility of the enzyme to the inactivation was assumed. It was found that the enthalpy-entropy compensation held for inactivation in 1-alcohols. © 2006 The Society for Biotechnology, Japan.

DOI： 10.1263/jbb.102.66

Oral administration of insulin included in fine W/O/W emulsions to rats 査読

M Shima, M Tanaka, T Fujii, K Egawa, Y Kimura, S Adachi, R Matsuno

FOOD HYDROCOLLOIDS 20 ( 4 ) 523 - 531 2006年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCI LTD

Fine W/O/W emulsions having controlled median diameters between 0.7 and 30 mu m were prepared using octanoic acid triacylglycerol (C8:0TG) and soybean oil as the oil phases. Transport enhancement of a model hydrophilic compound by the soybean-oil hydrolysates was investigated using Caco-2 model intestinal epithelial cells. The results were compared with those from in vivo experiments; in which rats were administered various types of W/O/W emulsions encapsulating insulin. Transport enhancement effect of the emulsions was evaluated by the blood-sugar level collected from the coccygeal vein. The pancreatic lipase-catalyzed hydrolysates of soybean oil showed high transport enhancement effects in Caco-2 model system, but the administration of insulin included in the W/O/W emulsion prepared with soybean oil had no hypoglycemic effect on rats. The transport enhancement effect of the hydrolysates of soybean oil in Caco-2 model system was attenuated by the coexistence of a coating material used in spray-drying process or triacylglycerol. On the other hand, administration of the W/O/W emulsions prepared with C8:0TG and encapsulating insulin showed a hypoglycemic effect on rats. Administration of the W/O/W emulsion having an oil-droplet median diameter of 2.3 mu m also showed the hypoglycemic effect in the earlier period than that of the coarse W/O/W emulsion having a diameter of 38 mu m. However, the emulsion with the diameter of 0.7 mu m exhibited no effect. These results suggested that the transport enhancement effect of the W/O/W emulsion prepared with C8:0TG depended on the size of the oil droplets, while too fine an emulsion had no such effect. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.foodhyd.2005.05.002

Conversion of Linoleic Acid to Its Conjugated Isomers in Subcritical Water 査読

USUKI Chisako, KIMURA Yukitaka, ADACHI Shuji

Japan Journal of Food Engineering 7 ( 2 ) 147 - 150 2006年6月

Kinetics of maltooligosaccharide hydrolysis in subcritical water 査読

Shabnam Haghighat Khajavi, Shuji Ota, Yukitaka Kimura, Shuji Adachi

Journal of Agricultural and Food Chemistry 54 ( 10 ) 3663 - 3667 2006年5月

記述言語：英語掲載種別：研究論文（学術雑誌）

The kinetics of the hydrolysis of maltooligosaccharides with a degree of polymerization (DP) of 3-6 in subcritical water was studied using a tubular reactor at temperatures between 200 and 260°C and at a constant pressure of 10 MPa. The maltooligosaccharide disappearance and product formation at residence times shorter than 50 s could be expressed by first-order kinetics. The rate constants for the hydrolysis of each maltooligosaccharide were evaluated. There was a tendency that the exo-site glucosidic bond was hydrolyzed faster than the endo-site one irrespective of the DP of the maltooligosaccharide. The hydrolysis of the maltooligosaccharides was consecutively preceded, and the time dependence of the hydrolysis for maltooligosaccharides with different DPs could be calculated by simultaneously solving the mass balance equations for all the possible saccharides. © 2006 American Chemical Society.

DOI： 10.1021/jf060117s

Decomposition kinetics of monoacyl glycerol and fatty acid in subcritical water under temperature-programmed heating conditions 査読

T Fujii, P Khuwijitjaru, Y Kimura, S Adachi

FOOD CHEMISTRY 94 ( 3 ) 341 - 347 2006年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCI LTD

The decompositions of monocaprylin, monocaprin, monolaurin and their corresponding fatty acids in subcritical water were measured under temperature-programmed heating conditions where the reaction temperature was linearly increased from room temperature to 350 degrees C at specified rates to estimate the activation energies E-i and the frequency factors k(i0) for the decompositions. The decompositions of both monoacyl glycerol and fatty acid obeyed first-order kinetics, and the decomposition of a monoacyl glycerol proceeded consecutively to form its constituent fatty acid and then further decomposition compounds. There was a tendency for both the E-i and k(i0) values for a monoacyl glycerol or fatty acid with a longer acyl chain to be smaller, and it was shown that the enthalpy-entropy compensation held for the decompositions of monoacyl glycerols and fatty acids as well as for those of fatty acid esters with various acyl and alkyl chains in subcritical water. (c) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.foodchem.2004.11.021

亜臨界水によるショ糖の加水分解に及ぼす塩の影響

Haghighat_Khajavi Shabnam, 大嶌臣, 中澤梨沙, 木村幸敬, 安達修二

化学工学会研究発表講演要旨集 2006 414 - 414 2006年

Hydrolysis of oligosaccharides in subcritical water

Shuji Adachi, Shabnam Haghighat Khajavi, Shuji Ota, Risa Nakazawa, Yukitaka Kimura

CHISA 2006 - 17th International Congress of Chemical and Process Engineering 2006年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Hydrolysis of trisaccharides consisting of different monosaccharides, such as 1-kestose, melezitose, raffinose and lactosucrose, was performed in the subcritical water in a temperature range of 150 to 230°C at 10 MPa. The hydrolysis of each trisaccharide proceeded consecutively. For all the trisaccharides, one of the two glycosidic bonds was preferentially hydrolyzed and the produced disaccharide was then hydrolyzed. The hydrolyses of trisaccharides except when the substrate contained β-Fru(2→ 1)β-Fru or α-Glc-(→ 2)β-Fru bond and their constituent disaccharides were expressed by the first-order kinetics of the substrate concentration. The hydrolysis of maltooligosaccharides with the degree of plomerization (DP) of 2 to 6 in the subcritical water also proceeded consecutively. The first-order kinetics was applicable for the decrease of the substrate at short residence times in the tubular reactor. The changes in the concentration of the substrate and maltooligosaccharides with the DPs shorter than the DP of the substrate were calculated by solving the mass balance equations for the saccharides simultaneously. The calculated curves expressed well the experimental results at the short residence times but deviated from the results at the longer residence times. There was site-specificity in the hydrolysis, and the rate constants for exo-site glucosidic bond were slightly greater than those for the endo-site bond.

Condensation reaction between angiotensin II and dicarboxylic acid in water at high temperature without any catalytic agent additive 査読

Takamitsu Asano, Atsushi Maeda, Yukitaka Kimura, Taro Takahashi, Akihiro Nakamura, Hirokazu Maeda, Shuji Adachi

Biotechnology Progress 21 ( 4 ) 1169 - 1174 2005年7月

記述言語：英語掲載種別：研究論文（学術雑誌）

The condensation reaction of angiotensin II and tartaric acid in water at 100-140°C proceeded without any added catalytic agent. One of the products, N-CO-tartarylangiotensin II, was confirmed by LC-MS, positive-ion MALDI-MS, and the fluorescamine method as a condensation product. The initial concentration of the substrates, temperatures, and initial pH affected the yield of the product. The higher concentrations and temperatures increased the concentration of the condensation product. The optimal pH for the condensation reaction was 3.0. The other C4 saturated dicarboxylic acids, malic and succinic acids, were also condensed by angiotensin II. © 2005 American Chemical Society and American Institute of Chemical Engineers.

DOI： 10.1021/bp050058n

Degradation kinetics of monosaccharides in subcritical water 査読

Shabnam Haghighat Khajavi, Yukitaka Kimura, Toshinobu Oomori, Ryuichi Matsuno, Shuji Adachi

Journal of Food Engineering 68 ( 3 ) 309 - 313 2005年6月

記述言語：英語掲載種別：研究論文（学術雑誌）

The degradation kinetics of the monosaccharides of both the aldohexose (glucose, galactose and mannose) and ketohexose (fructose and sorbose) types in subcritical water were studied using a tubular reactor in the temperature range of 180-260°C and at a constant pressure of 10 MPa. The relationship between the fraction of unreacted monosaccharide and the residence time could be expressed by the Weibull equation for all the monosaccharides at any temperature. The susceptibility to degradation was quite different among the saccharides. The activation energy and frequency factor were calculated from the Arrhenius equation and the enthalpy-entropy compensation was found to hold for the degradation of monosaccharides in subcritical water. The isokinetic temperature was similar to that for the hydrolysis of disaccharide. The conversion to 5-hydroxymethy-2-furaldehyde (HMF) and the decrease in pH of the effluent solution were measured and it was found that fructose had the highest value for both. © 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jfoodeng.2004.06.004

Kinetics on sucrose decomposition in subcritical water 査読

Shabnam Haghighat Khajavi, Yukitaka Kimura, Toshinobu Oomori, Ryuichi Matsuno, Shuji Adachi

LWT - Food Science and Technology 38 ( 3 ) 297 - 302 2005年5月

記述言語：英語掲載種別：研究論文（学術雑誌）

The kinetics of the sucrose decomposition in subcritical water was investigated using a flow-type reactor in the temperature range of 160-200°C and at a constant pressure of 10 MPa. The decrease in pH during the decomposition was linearly related to the logarithm of the conversion and significantly affected the decomposition rate. The sucrose decomposition was expressed by a kinetic equation of the autocatalytic type, where the decomposition rate of sucrose was proportional to the product of the concentrations of the remaining sucrose and acidic compounds, the most of which originated from the reacted sucrose. The equation was applicable to the sucrose decomposition at its feed concentrations from 5-250 g/l and at different pHs. The conversion of sucrose to glucose and fructose almost stoichiometrically proceeded in the stated temperature range. It was also indicated that the pH of the reaction mixture played an important role in the sucrose decomposition in subcritical water. © 2004 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.lwt.2004.06.005

Enhancement in transport of a hydrophilic marker through intestinal epithelial cell (Caco-2) monolayer by W/O/W multiple emulsion containing C8TG 査読

M Shima, M Tanaka, Y Kimura, S Adachi, R Matsuno

FOOD HYDROCOLLOIDS 19 ( 2 ) 321 - 328 2005年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCI LTD

A W/O/W emulsion containing octanoic acid triacylglycerol (C8TG) was prepared as a carrier for hydrophilic bioactive substances. The absorption enhancement effect of the hydrolysates of C8TG in the W/O/W emulsion was investigated by measuring the transport of a hydrophilic marker through the intestinal epithelial (Caco-2) cell monolayer. First, the concentrations of gall and lipase in an artificial digestive fluid, of which the integrity of the Caco-2 monolayer was not affected, were both determined to be 0.1% (w/v). The W/O/W emulsion including the hydrophilic marker molecule was hydrolyzed by the artificial digestive fluid and the apparent permeability of the hydrophilic marker substance was measured. In order to clarify the components affecting the transport enhancement, octanoic acid monoacylglycerol (C8MG) was mixed with a W/O/W emulsion at the same concentration as that in the emulsion hydrolyzed by the digestive fluid. The dependence of the apparent permeability on the C8MG concentration was the same for both emulsions, indicating that C8MG, hydrolyzed from the oil phase of the W/O/W emulsions, played an important role in the transport enhancement effect of the W/O/W emulsions. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.foodhyd.2004.07.004

Continuous synthesis of 6-O-linoleoyl hexose using a packed-bed reactor system with immobilized lipase 査読

Jie Chen, Yukitaka Kimura, Shuji Adachi

Biochemical Engineering Journal 22 ( 2 ) 145 - 149 2005年1月

記述言語：英語掲載種別：研究論文（学術雑誌）

6-O-Linoleoyl mannose, glucose and galactose were continuously synthesized in acetone using a packed-bed reactor system with immobilized-lipase from Candida antarctica. The high solubility of mannose in acetone resulted in the highest product concentration among the hexoses tested. The factors affecting the product concentration such as the linoleic acid concentration in the feed, the residence time in the reactor and the reaction temperature were examined. Although the product concentration was higher at the higher linoleic acid concentration, a concentration four times the solubility of hexose at a given temperature seemed to be proper. The product concentration became almost constant at a residence time in the reactor longer than 20 min. Linoleoyl mannose was continuously synthesized at 60 and 70°C, and the operation at 60°C was indicated to be preferable to that at 70°C for long-term steady synthesis. © 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.bej.2004.09.010

Synthesis of linoleoyl disaccharides through lipase-catalyzed condensation and their surface activities 査読

Jie Chen, Yukitaka Kimura, Shuji Adachi

Journal of Bioscience and Bioengineering 100 ( 3 ) 274 - 279 2005年

記述言語：英語掲載種別：研究論文（学術雑誌）

Monolinoleoyl trehalose, maltose and cellobiose were synthesized by Candida antarctica lipase-catalyzed condensation in an organic solvent with a low water content. The use of a mixture of pyridine and tert-butanol as the reaction medium resulted in a high product concentration on the order of mmol/l for the synthesis of linoleoyl trehalose and maltose. The highest product concentration was achieved with the 0.4 volumetric fraction of pyridine. Linoleoyl cellobiose was also synthesized although its concentration was approximately one tenth the concentrations of linoleoyl trehalose and maltose. The surfactant properties of linoleoyl trehalose, maltose and cellobiose were measured. Among the esters, linoleoyl trehalose showed the strongest surface activity. © 2005, The Society for Biotechnology.

DOI： 10.1263/jbb.100.274

Kinetics of Moisture-induced-discoloration of L-Ascorbic Acid Powders 査読

Lan-hsin Hung, Yukitaka Kimura, Shuji Adachi

NIHON SHOKUHIN KOUGAKUKAISHI (Japan Journal of Food Engineering) 6 ( 4 ) 289 - 296 2005年

記述言語：英語掲載種別：研究論文（学術雑誌）

The discoloration of L-ascorbic acid (vitamin C) powders with a water content of 1 to 10% (w/w) during storage at a temperature of 60 to 90°C was investigated by monitoring the absorbance of L-ascorbic acid solutions at 360, 450 and 500 nm. The discoloration reaction of the L-ascorbic acid powders was expressed by the modified Weibull equation under any condition. The rate constant, the shape constant and the maximum absorbance were estimated based on the equation. The temperature dependence of the rate constant was expressed by the Arrhenius equation under every storage condition, and the values of the activation energy and frequency factor increased with the increase in the water content. Although the shape constant depended on the wavelength at which the discoloration was observed, it was independent of the temperature. The maximum absorbance at every wavelength was expressed as functions of the water content of L-ascorbic acid powders and the storage temperature. These results enable us to estimate the discoloration of L-ascorbic acid powders under any condition, while the water content and the temperature would be limited in the ranges of 0 to 10% (w/w) and 60 to 90°C, respectively. © 2005, Japan Society for Food Engineering. All rights reserved.

DOI： 10.11301/jsfe2000.6.289

Preparation of finely dispersed O/W emulsion from fatty acid solubilized in subcritical water

P Khuwijitjaru, Y Kimura, R Matsuno, S Adachi

JOURNAL OF COLLOID AND INTERFACE SCIENCE 278 ( 1 ) 192 - 197 2004年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ACADEMIC PRESS INC ELSEVIER SCIENCE

A novel method for preparing a finely dispersed oil-in-water emulsion is proposed. Octanoic acid dissolved in water at a high temperature of 220 or 230 degreesC at 15 MPa was combined with an aqueous solution of a surfactant and then the mixture was cooled. When a nonionic surfactant, decaglycerol monolaurate (ML-750) or polyoxyethylene sorbitan monolaurate (Tween 20), was used, fine emulsions with a median oil droplet diameter of 100 nm or less were successfully prepared at ML-750 and Tween 20 concentrations of 0.083% (w/v) and 0.042%, respectively, or higher. The diameters were much smaller than those of oil droplets prepared by the conventional homogenization method using a rotor/stator homogenizer. However, an anionic surfactant, sodium dodecyl sulfate, was not adequate for the preparation of such fine emulsions by the proposed method. Although the interfacial tensions between octanoic acid and the surfactant solutions were measured at different temperatures, they were not an indication for selecting a surfactant for the successful preparation of the fine emulsion by the proposed method. (C) 2004 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.jcis.2004.05.032

Solubility of oleic and linoleic acids in subcritical water 査読

Pramote Khuwijitjaru, Yukitaka Kimura, Ryuichi Matsuno, Shuji Adachi

Food Science and Technology Research 10 ( 3 ) 261 - 263 2004年8月

記述言語：英語掲載種別：研究論文（学術雑誌）

The solubility of oleic and linoleic acids in water was measured in the range from 60°C to 230°C at 15 MPa. The solubility of oleic acid was almost the same as that of linoleic acid in this range, and the solubility of the fatty acids was higher at higher temperature. The logarithm of the solubility of the fatty acids was related to the reciprocal of the absolute temperature by a linear equation with a negative slope at temperatures above 150°C, and the enthalpy of the solution of each fatty acid in the liquid state in water was estimated to be 122 kJ/mol.

DOI： 10.3136/fstr.10.261

Solubility of oleic and linoleic acids in subcritical water 査読

P Khuwijitjaru, Y Kimura, R Matsuno, S Adachi

FOOD SCIENCE AND TECHNOLOGY RESEARCH 10 ( 3 ) 261 - 263 2004年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：KARGER

The solubility of oleic and linoleic acids in water was measured in the range from 60 degrees C to 230 degrees C at 15 MPa. The solubility of oleic acid was almost the same as that of linoleic acid in this range, and the solubility of the fatty acids was higher at higher temperature. The logarithm of the solubility of the fatty acids was related to the reciprocal of the absolute temperature by a linear equation with a negative slope at temperatures above 150 degrees C, and the enthalpy of the solution of each fatty acid in the liquid state in water was estimated to be 122 kJ/mol.

DOI： 10.3136/fstr.10.261

Kinetics on the hydrolysis of fatty acid esters in subcritical water 査読

P Khuwijitjaru, T Fujii, S Adachi, Y Kimura, R Matsuno

CHEMICAL ENGINEERING JOURNAL 99 ( 1 ) 1 - 4 2004年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE SA

Hydrolysis of fatty acid esters with different acyl and alkyl chains in subcritical water was examined over a temperature range of 483-543 K in a batch reactor. The concentrations of fatty acid esters were sufficiently low to assume a homogeneous reaction at every temperature. The hydrolysis of every fatty acid ester at any temperature obeyed first-order kinetics. The rate constant was observed at various temperatures, and the apparent activation energy and frequency factor were evaluated according to the Arrhenius equation for each fatty acid ester. Steric hindrance of the acyl and alkyl chains was found to increase the activation energy of the hydrolysis. The enthalpy-entropy compensation held in the hydrolysis of the fatty acid esters tested. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cej.2003.08.002

Effect of the hydrophilic surfactants on the preparation and encapsulation efficiency in course and fine W/O/W type emulsions

M Shima, Y Kobayashi, Y Kimura, S Adachi, R Matsuno

COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS 238 ( 1-3 ) 83 - 90 2004年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE BV

Although the surfactant plays an important role in the preparation of a water-in-oil-in-water (W/O/W) emulsion, its concentration has been determined empirically. We investigated the location of a hydrophilic surfactant in a coarse W/O/W emulsion and a membrane-filtered fine emulsion. At first. appropriate concentrations of some hydrophilic surfactants to prepare a W/O/W emulsion were investigated from the viewpoints of the median diameter of the oil droplets and the encapsulation efficiency of a hydrophilic substance in the inner-water phase. The location of the surfactants and oil was examined for the W/O/W emulsions, prepared using polyglycerol monolaurate as a hydrophilic surfactant in the outer-phase solution at 1-10% (w/v) and octanoic acid triacylglycerol, which contained hexaglyceryl condensed ricinoleate as an oil-phase surfactant in the oil phase. The median diameter of the oil droplets in the W/O/W emulsion reached a minimum value at 3% (w/v) decaglycerol monolaurate (ML-750), and was constant over 4% (w/v). The excess decaglycerol monolaurate, that was not adsorbed on the oil-water interface was distributed to the outer-water and oil phases. The oil and hydrophobic surfactant were dissolved in the outer-phase solution at high concentrations of the hydrophilic Surfactant. These results suggest that the hydrophilic-surfactant concentration appropriate for preparing the W/O/W emulsion would be 3% (w/v) in the outer-phase solution and that the location of the components in the W/O/W emulsion would also be useful in estimating the adequate concentration of the surfactant. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.colsurfa.2004.02.018

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